Marines arrested Miguel Ángel Treviño Morales, aka Z-40, after intercepting his pick-up truck with a helicopter a few miles (km) from his home town of Nuevo Laredo on the US border, government spokesperson Eduardo Sánchez said in Mexico City.
"Not a single shot was fired," Sánchez reporters.
The Zetas have been blamed for many of the worst atrocities carried out by Mexican drug gangs, acts that have sullied the country's name and put fear into tourists and investors alike.
Following a tide of gang-related beheadings, massacres and gunfights that have claimed more than 70 000 lives since the start of 2007, President Enrique Peña Nieto said his number one priority was to restore stability when he took office in December.
Murders have fallen slightly, according to official statistics, but violent crime is still rampant in parts of Mexico and, until now, the new government had few outstanding successes to celebrate in its campaign to pacify the country.
Treviño Morales (40) was caught with two associates following a months-long operation to track him down, Sánchez said. Authorities also seized more than $2-million dollars in cash and a cache of arms in the operation, he said.
Treviño Morales's capture follows a string of blows in 2012 against the Zetas, whose previous leader was killed by marines in a firefight in northern Mexico last October.
Among the most shocking incidents pinned on the Zetas have been massacres of migrant workers, an arson attack on a Monterrey casino in 2011 that killed 52 and the dumping of 49 decapitated bodies near to the same city last year.
The government said Treviño Morales was wanted for a litany of crimes including murder, torture, money laundering and ordering the kidnapping and execution of 265 migrants near the northern town of San Fernando. The bodies of dozens of murdered migrant workers were recovered there in both 2010 and 2011.
By the time Peña Nieto took power, much of Mexico was worn out by the bloodshed under his predecessor Felipe Calderón.
Calderón, a conservative, had staked his reputation on bringing Mexico's powerful drug gangs to heel, sending in the armed forces to regain the upper hand.
Though his forces captured or killed many of the top capos, the bloodletting increased, led by the Zetas excesses.
Founded by army deserters in the late 1990s, the Zetas initially acted as enforcers for the Gulf Cartel. But cracks began to appear and the rupture was sealed in early 2010, setting off the most violent phase in Mexico's drug war.
The US State Department has offered a reward of up to $5 million for information leading to Treviño Morales's capture.
Security experts said Treviño Morales, who was born in Nuevo Laredo, took over the Zetas after the marines killed the cartel's longstanding commander, Heriberto Lazcano, in October.
Unlike most top Zetas, Treviño Morales had no military background, building up a power base within the gang as a financial fixer and logistics expert, and helping extend its operations running cocaine and crystal meth into the United States and Europe.
Treviño Morales's reputation for extreme violence also helped cement his rise.
"He's the most sadistic of them," US political scientist and Zetas expert George W Grayson said. "He really gets off on inflicting diabolical pain on people."
In the months leading up to Lazcano's death, rumours of a split in the cartel were rife following a massacre of Zetas reportedly carried out by other members of the gang in the central city of San Luis Potosi.
Not long before Lazcano was killed in Coahuila state, banners accusing Treviño Morales of being a "Judas" to the Zetas leader began to appear, fueling talk the gang was splintering.
Then, in the space of a few weeks, Zetas staged a mass jailbreak on the US-Mexican border, assassinated the son of a top politician, and Lazcano was killed. Treviño Morales was in control.
Believed to have been born on June 28 1973, Treviño Morales spent many of his formative years in Dallas, doing menial work that led him to be labelled "car washer" by some detractors.
Turning to criminal enterprise, Treviño Morales and his brothers set up a sophisticated money-laundering ring in the United States using race horses as a front.
In June 2012, hundreds of FBI agents across the United States raided their stables, arresting Treviño Morales's older brother Jose. According to the FBI, the stables received more than $1-million a month from Mexico and had more than 300 stallions. One of the horses was called Number One Cartel.
Treviño Morales, whose younger brother Omar was one of his top lieutenants, sought to expand the gang's power by taking the Zetas' fight with Mexico's most-wanted drug lord, Joaquin "Shorty" Guzman, onto the latter's home turf in Sinaloa state.
In so doing, Treviño Morales helped escalate the levels of gang violence then convulsing Mexico, which rose notably after the Zetas split with their former bosses, the Gulf Cartel. – Reuters